What Is the Scientific Evidence for Detoxification?
In general, there is little to no scientific support for detoxification methods. Aside from specific toxicities such as lead or arsenic, medical researchers have observed no general phenomenon of toxification. For this reason, it is difficult to scientifically validate whether detoxification methods actually work.
Most detoxification approaches essentially remain unexamined, rather than proven or disproven, and rely on reasonable concepts but no hard evidence for their justification. Mercury-filling removal is a typical example. Many alternative practitioners believe that the mercury in silver fillings is a cause of numerous health problems and should be removed to prevent or treat disease. However, although it is a matter of indisputable fact that mercury can be toxic, scientific evaluation generally indicates that mercury levels in people with mercury fillings are far below those necessary to cause toxic symptoms. ^ Anti-mercury advocates respond that some people are sensitive to mercury in very low amounts, and that those people will therefore benefit from filling removal even if they are not experiencing actual toxicity. This could certainly be true. However, despite numerous unreliable anecdotes, there is as yet no meaningful evidence that removing mercury fillings can treat or prevent any disease. (For information, see Why Does This Database Rely on Double-blind Studies? )
Much the same can be said about all of the other popular detoxification methods. However, in the case of one form of detoxification, colon cleansing, the theory behind the technique is definitely wrong. According to this nineteenth-century theory known as “colon health” or “colon hygiene,” years of bad diet cause the colon to become caked with layer upon layer of accumulated toxins. This accumulation is said to resemble sedimentary rock. High colonics, which are essentially enemas that reach far up into the large intestine, are said to release the accumulated buildup and thereby restore health.
However, in recent decades, physicians have performed colon examinations to search for colon cancer in millions of patients, and their findings do not support the theory. Most of the patients given these examinations are at least middle-aged, and not very many have devoted their lives to healthy diets and clean colons. According to the colonic hygiene theory, colon examinations on such patients should turn up concrete-like deposits. However, all that shows up during a typical colonoscopy is fresh, pink flesh. Unfortunately, proponents of colonics do not seem to have assimilated this information; they continue to recount theories about the colon that were shown to be untrue decades ago.
The concept of detoxification plays a major role in many schools of alternative medicine, including Ayurveda , naturopathy and chiropractic . In this context, the term refers to a belief that toxins accumulated in the body are a major cause of disease, and that health can be promoted by removing them through various means.
The toxins referred to in this theory are said to have several major sources:
- Chemicals added to processed foods, such as preservatives
- Chemicals that enter the food chain through the use of pesticides, artificial fertilizers, and drugs given to food animals
- Toxins produced in the intestines due to improper digestion
- Toxins produced in the bloodstream due to stress
- Pharmaceutical medications, nearly all of which are regarded as essentially toxic by proponents of detoxification
- Toxins present in the general environment, such as automobile exhaust, cigarette smoke, the aluminum in antiperspirants, and the formaldehyde released by new carpet
- Toxins in water
- Toxins introduced through the use of mercury fillings and other medical procedures
These toxins are said to cause a wide variety of chronic illnesses, from multiple sclerosis and migraine headaches to cancer and rheumatoid arthritis , and alternative practitioners use various methods with the intention of removing the toxins. One such recommendation has made it into conventional wisdom: drinking at least a quart (or a half-gallon) of water per day. Other detoxification methods include fasting (on juice, water, fruit, or brown rice), using “cleansing” herbs and supplements (such as olive oil and lemon juice to flush the liver, dandelion root to purge the gallbladder, or psyllium seed to cleanse the colon), taking high colonics, receiving intravenous vitamin C , and/or removing mercury fillings.
Removing toxins is often said to cause a temporary flare-up of illness. This reaction is generally interpreted as a positive sign, but also as a call for careful medical management to avoid causing harm on the way to healing.